[sorry, I messed up the posting order!]
Tonks turned from blasting a lizard, which made at least five that she'd incapacitated, and probably a similar number by Luna. This left five to jump on Marcus. Not to mention, there seemed to be a couple more of the creatures starting to stalk up. Her eyes narrowed as she watched Marcus be dogpiled.
She didn't even think. It was the mad she loved being crushed and possibly hurt under there! No words would come to mind, simply a feral scream. For the first time, she understood what could lead someone to use an Unforgivable. She knew some of the Aurors did when needed, but she never had. But with the rage and fear going through her, she knew she could make such a spell work.
She chanelled that energy differently, however, and inside pointed her wand right at the creatures. "Confringo!" The Blasting Charm was a potent enough weapon in its own right, but since she was so incredibly angry, it seemed to power it up. She'd targeted it on one of the lizards, but all of them flew off to fall limply to the ground.
"Are you alr-- there's more!" She pointed as three more charged them, apparently undaunted by the 15 they'd already killed. "Luna, Marcus!"